#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
	int a = 0;
	int b = 0;
	int c = 0;
	while (scanf("%d %d %d", &a, &b, &c) != EOF)
	{
		if (a + b > c && a + c > b && b + c > a)
		{
			if (a == b && b == c)
				printf("Equilateral triangle!\n");
			else if (a == b && a != c || a == c && a != b || b == c && c != a)
				printf("Isosceles triangle!\n");
			else
				printf("Ordinary triangle!\n");
		}
		else
			printf("Not a triangle!\n");
	}
	return 0;
}